Analysis On Stress And Deformation Of High Constructing Earth-Rock Dam With Consideration Of Materials Compactness

A number of high earth-rock dams are being constructed in China, which takes more attention to the safety and stability of dams. Crack caused by non-uniform distortion, is one of the important reasons of dam destruction, so it is necessary to analyze dam stress and deformation in order to find the sites that may have cracks and make early warming for the potential accidents. In traditional finite element method, dam material density obtained by experiment is always set with the same value in a district. But actually, the material density has great relationship with the compaction condition, so it is not accurate for calculating dam stress and deformation with the same density value at any location. In this paper, a method of analyzing stress and deformation of high constructing earth-rock dam with consideration of materials compactness is presented. The main contents and achiements of the paper are as follows:(1) A brief introduction is made for real-time compaction quality monitoring system and the method to get compaction operation parameters. Then we established a multiple regression model between density and independent variables that obtained from the real-time quality-monitoring system, test pits and aggregate's data. Based on the multiple regression model, the density value on any grid can be obtained, which will provide data foundation for finite element method.(2) A method that takes the grid density on work unit to finite element is proposed by the dam grid density. Based on ANSYS software, using its secondary development, macro command to set finite element density is written.(3) A method to calculate stress and deformation with the consideration of compaction quality is proposed. This paper makes use of ANSYS PARAMETER DESIGN LANGUAGE (apdl) to write Duncan-Chang model in ANSYS first. Then based on the written Duncan-Chang model, coupling with dam density, this paper computes the stress and deformation of earth-rock dam, then establishes post-processing program.(4) Taking one earth-rock dam as a practical application case by using the mentioned method example, the stress and deformation analysis is done and the corresponding isogram can be obtained. Meanwhile, deformation on any position can be extracted to compare the calculated value with measured. The comparative results shows that vertical deformation with consideration material compactness is more accurate to the uniform density, meanwhile the horizontal displacement and stress are consistent with the measured value with the two calculation condition, which indicate the effectiveness of the above-mentioned method.